A New Genus of Fresh-water Isopoda. 129 



Maxillipeds (Fig. 9). — The maxillipeds are almost identical with 

 those oijanira maculosa^ Leach, but the epipodite (or epignath) 

 has not the outer edge angular in the middle, but rather concave. 

 As in that species, the second and third joints of the " palp " are 

 not much expanded, in contrast to Janiropsis, in which they are 

 veiy broad. 



Peraeopods. — The peraeopods are rather long, subequal in form, 

 and each succeeding pair slightly increases in length. Fig. 10 

 illustrates the first, and Fig. 12 the last pair. A description of 

 the tii'st will suffice for the remainder, except in respect of the 

 setae and spines. The first pair may be, but if so it is very 

 feebly prehensible, for the carpus is not sjiecially developed nor 

 difiers from the succeeding pair, as in /antra. On the postero- 

 distal angle of the propodos, and also the carpus, there are one or 

 more plumose sensory setae, and along the inner margin of the 

 propodos there is a row of six stout spines of curious shape (Fig. 

 11). These are rather broad at the base, but narrow to an acute 

 end ; at about half their length, on the outer side, there arises a fine 

 filament or seta which curves outward somewhat, and extends as 

 far as the end of the spine. The dactylos is long, about one- 

 third the length of the propodos, slightly curved, and terminates 

 in a large single unguis, and on the inner margin, at its base, 

 there is a short secondary unguis. The remaining joints are 

 subequal in form to Janira and other allied genera. 



Pleopods. — The pleopods are of normal form. The operculum 

 is as large as the caudal segment, and covers the whole of its 

 ventral surface. The others require no particular description, a 

 reference to (Figs. 14, 15 and 16) will sufficiently explain them. 



Uropods. — The form of the uropods has been sufficiently 

 explained in the specific description. There are short scattered 

 setae on the peduncles, but the rami are almost bare except 

 on the rounded extremities, from each of which springs a tuft of 

 very long setae 



Male. 



Fig. 2 illustrates a small male of 2-5mm. length but is similar 

 in form to one examined of 3mm. which was the largest obtained. 

 The shape of the cephalon and succeeding four segments is 

 similar to those of the female, but the remaining segments, 



